Yz 250f won't rev

had my bike running mint and rode it for like 3 hours and I went to ride it after about 2 or 3 weeks of sitting due to bad weather and it starts fine and idles fine but as soon as I give it gas it dies. If I give it choke and let it idle and go WOT with choke on it will rev up for a little bit and die. Any suggestions? Gotta be a carb problem. Too lean I'm guessing? Maybe someone played with my fuel screw.
 
Plugged main maybe, Let me be the first to say, buy a manual, and clean the carb. Actually that happened to my 450, but it was a broken E Clip on the needle. Either way, open up the carb.
 
Maybe your fuel screw fell out. I've seen that happen.
Whenever I'm done riding I like to shut off the gas and run the bowl dry. Even if it only going to be sitting for a week. I'd link you to an online download manual, (which is VERY easy to find btw) but quite honestly if you don't have one by now your judgement is suspect. listen, you'll read instructions on a box of
Macaroni and cheese but not
for your motorcycle. Cmon.

Actually the manual in this case won't do you much good, the carb section is brief and really is good for the exploded view of all the parts you will surely lose when you open it, but the tuning section is fairly universal to carbs in general so read up.

..an hell just take the whole damn thing apart an spread it out on the garage floor.
 
I just read my own reply damn I was salty that day! No offense intended, I a ctually just assumed you didn't have a manual. The spotless brass jets are spotless on the outside. Hold them up to the light and you can see the crust inside. Guitar strings are great for cleaning them. Spray carb cleaner and be careful not to try and stab something in that doesn't fit. Also, while you have it apart make sure the float is set properly. Is your choke pulled? lol
 
I just read my own reply damn I was salty that day! No offense intended, I a ctually just assumed you didn't have a manual. The spotless brass jets are spotless on the outside. Hold them up to the light and you can see the crust inside. Guitar strings are great for cleaning them. Spray carb cleaner and be careful not to try and stab something in that doesn't fit. Also, while you have it apart make sure the float is set properly. Is your choke pulled? lol

I inspected all jets and cleaned anyway. I'm gonna pull the fuel shut off out and check the screen. It's obviously not getting fuel some how. But I'll try your method too. Thanks. Ill update you guys
 
Usually the smaller fuel/air circuits will keep you from idling clean or easy starting but shouldn't overly affect your wide open consumption of fuel. It may not rev quickly with great response but shouldn't just die when you throttle it. Id guess it's probably something besides ethanol crust.
Keep looking you'll find it. Good luck
 
The fuel screw is missing the spring. Someone or my self must have fucked with it and put it back in fully bottomed out, thus the bike getting no fuel
 
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